Manufacture of plates or shaped sheets having a base of mineral fibers particularly glass fibers

ABSTRACT

The invention contemplates the homogeneous distribution of hard granules or particles throughout a mass of resin-coated mineral fibers to produce structural units in the form of sheets or slabs composed of the mass of mineral fibers in lattice-work form, particularly glass fibers, agglomerated with the dried and cured resin binder and having interspersed in the meshes of the mass, the separate hard and indeformable particles, either in solid form, such as sand, or in porous form, such as perlite or vermiculite, which render the structural units strongly resistant to physical deformation while enhancing the heat-insulating characteristics thereof.

United States Patent Inventors ClaudeJumentier La Celle Saint Cloud,(Yvelines); Alain Bonnet, Clermont (Oise), both of France Appl. No.726,706

Filed May 6, I968 Patented Oct. 26, I971 Assignee Compagnie deSaint-Gobain Neuilly-Sur-Seine (Seine), France Priority May 11, 1967France 106046 MANUFACTURE OF PLATES 0R SHAPED SHEETS HAVING A BASE 0FMINERAL FIBERS, PARTICULARLY GLASS FIBERS 18 Claims, 17 Drawing Figs.

US. Cl 156/285,

156/62.2, 156/276 Int. Cl B32b 31/06 Field of Search 156/276,

[56] References Cited UNITED STATES PATENTS 3,137,60l 6/1964 Menzeri56/276 3,144,376 8/1964 Plumberg et al 156/276 Primary Examiner-Carl D.Quarforth Assistant Examiner-S R. Hellman Attorneys-Samuel Lebowitz,Dale A. Bauer, John L.

Seymour and Bauer and Seymour ABSTRACT: The invention contemplates thehomogeneous distribution of hard granules or particles throughout a massof resin-coated mineral fibers to produce structural units in the formof sheets or slabs composed of the mass of mineral fibers inlattice-work form, particularly glass fibers, agglomerated with thedried and cured resin binder and having interspersed in the meshes ofthemass, the separate hard and indeformable particles, either in solidform, such as sand or in porous form, such as perlite or vermiculite,which render the structural units strongly resistant to physicaldeformation while enhancing the heat-insulating characteristics thereof.

PATENTEnnm 26 I971 3,616,030

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INVENTORS 61 4005 JZ/Mf/Vf/EK 1414/ Bow/v57- A ORNEY PATENTED am 2 sIQYI SHEET 5 0F 8 INVENTORS C2 ,4UOE JZ/MEA/ mse 444ml BOA/M57 ATTORNEYPATENTEBUET 26 I971 3,616,030

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sum 80F a Y INVENTORS (1,4005 J/uewr/ae I 42 44 .4/A/ 1304/4/57 ATTORNEYMANUFACTURE OF PLATES R SHAPED SHEETS HAVING A BASE 0F MINERAL FIBERS,PARTICULARLY GLASS FIBERS The invention relates to the production ofplates or sheets shaped from a mass of mineral fibers, particularlyglass fibers, agglomerated by a binding agent, which present at the sametime both a high insulating capacity as well as a high degree ofindeformability. According to one characteristic of the invention, theseplates or shaped sheets are constituted by a latticework or network offibers which are joined to each other by a binder and by solid andindeformable particles in the form of unitary granules which areinterlocked and encompassed separately in the meshes of the fibernetwork and distributed in a homogeneous fashion therein.

It is another characteristic of the invention that the particles whichare employed are at the same time hard, whole and indeformable, whilebeing either solid or porous.

It has been determined that while the products of the invention presenta very low tendency to deformation, particularly compression, theyretain strongly the high heat-insulating capacity inherent in the porousstructure of a mass of mineral fibers. This preservation of the highinsulating quality is due to the fact that the hard particles orgranules are in contact with the fibers of the meshes which encompassthem only along points or lines of slight length, and thus there ispractically no formation of thermal conducting paths or bridges betweenthe particles and the fibers.

The high degree ofindeformability of the products of the inventionarises from the fact that each particle impedes the local deformation ofthe network in which it is enclosed, and that by reason of thehomogeneous distribution of the particles in the entire mass, thedeformation of the whole of the mass is prevented by the presence of allof these particles.

in a general way, it is possible to select the average granulometry ofthe particles which are used, as a function of the volumetric mass whichis related to the mass of fibers. ln all cases, the size of theparticles or granules should be such that they are enclosed within themeshes ofthe network formed by the fibrous mass. lf these meshes arevery fine, small granules or particles of light granulometry are used;if the meshes are large, particles oflarger dimensions may be used.

According to one embodiment of the invention, the fibers constitutingthe network may have a mean diameter between 3 microns and 16 microns;the apparent volume-mass characteristic or density of this fibrous massmay range between 25 Kg. and 200 Kg. per cubic meter, and preferablybetween 35 Kg. and 100 Kg. per cubic meter, and preferably between 35Kg. and 100 Kg. per cubic meter; the granulometry of the solid, whole,indeformable particles may be of the order of 0.10 mm. to 0.6 mm. andthe proportion by volume of the mass of particles may be of the order of2 percent to 20 percent and preferably 3 percent to percent of the totalvolume ofthe product,

According to another embodiment of the invention, the apparentvolume-mass characteristic or density of the fibrous network may rangebetween 35 Kg. and 100 Kg. per cubic meter, and the particles enclosedin the meshes of this network may be constituted by grains of sand ofagranulometry of the order of0.l0 mm. to 0.40 mm.

Instead of sand, other solid particles may be used, for example, crushedglass, crushed rock, melted coal ashes, etc. The condition which theseparticles must always meet being that they are hard and indeformable.

Another improvement results from the use of hard and indeformablegranules which include empty spaces. Advantageous characteristics areimparted to the structural units of the invention by the use of hardporous or foamed mineral particles, such as perlite or vermiculite. Theproducts resulting from the use of such components are characterized byextremely lightweight, high insulating capacity and a high degree ofindeformability.

When use is made of fibrous masses having a slightly elevated specificdensity, the presence of these particles therein, particularly perlite,result in products which evidence it strong resistance to deformation,particularly compression.

In the modes of execution of the invention with hard porous granules,the constituent fibers of the network may have a mean diameter rangingbetween 3 microns and I6 microns, the apparent volume-masscharacteristic or density of this network may range between 8 Kg. andKg. per cubic meter, preferably between 8 Kg. and 50 Kg. per cubicmeter, with the granulometry of the granules being above 0.l mm., andpreferably between 0.5 mm. and 5 mm., and the proportion in volume ofthe mass of particles being of the order of 3 percent to 80 percent, andpreferably between 10 percent and 50 percent of the total volume of theproduct.

The quantity of particles which is used per unit of volume of the finalproduct depends on the density of the product and the mechanicalproperties which are sought to be attained. To obtain identicalmechanical properties, for example, identical resistance to crushingunder load, it is desirable that the proportion of particles be greateras the quantity of constituent fibers per unit of volume is lower.Otherwise, for a like quantity of fibers per unit of volume, the greaterproportion of granules results in a higher degree of mechanicalresistance.

It is the object of the invention to provide a method of producingstructural units in the form of plates or shaped sheets of highinsulating capacity and indeformability, as described above. This methodconsists in introducing the hard and indeformable particles, either insolid or porous form, throughout the mass of fibers in homogeneousfashion, by flowing the particles and projecting them into the mass offibers which is treated with a binding agent, by the action of a gaseouscurrent, and by then reducing the volume of said mass in such a way thatthe particles are completely enclosed and interlocked between the fibersafter the binder sets. The reduction of volume may be effectedadvantageously by exerting a suction effect through the mass of fibers.

As a variation, the method may also be executed by introducing all orpart of the binder together with the solid or porous granules orparticles, into the mass of fibers. Thereby a better distribution of thebinder within the network of fibers is obtained. It has been determinedthat the binder introduced with the particles moves from the surfaces ofthe particles towards the fibers and assures the joining of these fibersat their crossing points without the binder remaining in contact betweenparticles and fibers, thereby avoiding all thermal bridges between them.

ln accordance with the invention, provision is made to vary the quantityof granules or particles introduced into the mass of fibers, which maybe varied in dependence upon the mechanical characteristics sought to beimparted to the product.

The invention contemplates many different devices for executing theprocedures described above. These devices comprise a distributor,wherefrom the particles flow by gravity, and members, such as blowingnozzles, for producing gas jets, which act on the particles to projectthem into the mass of fibers and distribute them homogeneously in thelatter.

According to one embodiment of the apparatus, the projection ofparticles takes place on one side of the mass of fibers.

According to another embodiment of the invention, the distributor andblower members are arranged around the mass of fibers issuing from theproduction apparatus, and there is provided, under the blower members,an oscillating nozzle or conduit into which passes the mass of fiberswith the particles which have been incorporated in it. The oscillationsof the nozzle or conduit make possible the regular distribution offibers on the cloth or other receiving surface onto which the mass isprojected for the formation of a mat or sheet.

it is the particular objective of the arrangements in accordance withthe invention to secure an effective homogeneous distribution of theparticles in the mass of fibers. This may be attained by introducing thegranules or particles into the gaseous currents in. the form ofa sheetof particles which flows in a homogeneous and uniform fashion. This maybe accomplished by feeding the particles onto a distributing surfacesurrounding the mass of fibers, which particles flow in a homogeneousand uniform fashion from the distributing surface in the form of a sheetwhich is subjected to the action of the gaseous currents. One of thefeatures of the invention is that the particles move freely on thedistributing surface in forming a natural flow, h y I When the fibersare produced by a rotary centrifuge, of the type well known in the art,the attenuated fibers gravitate in the form of a torus-shaped masshaving a rotary movement. In this case, the particles may be projectedinto the mass of fibers by imparting a rotary movement to the annularsheet of granules which has a component in a direction opposite to thedirection of rotary movement of the mass of fibers.

Also, the apparatus in accordance with the invention comprises adistributing member in the form of a crown surrounding the mass offibers with elements which supply the particles onto the crown in theformof threads or streams. The crown has an inclination or slope atleast equal to the slope of collapse or the angle of repose of thegranules so that the several streams form sheets, which, by virtue ofthe positioning of the points of supply of the particles, merge togetherat the rim of the distributor crown to form a continuous and homogeneouslayer of uniform thickness, which is then projected onto the mass offibers by the blowers.

In accordance with another feature of the invention, the elements whichsupply the particles onto the distributor crown are formed by conduitswhich communicate with an apparatus which feeds the particles through aplurality of orifices, beyond which, the thickness of the beds or layersof particles issuing from the several orifices, is maintainedsubstantially the same. v w

In accordance with another feature of the invention, the apparatussupplying the particles may consist of parallel tubes fitted with screwconveyors which advance and circulate the particles and feed them instreams or layers of substantially constant and adjustable thicknessbeyond the orifices which supply the conduits. The latter are preferablyin the form of sluices or channels. In order to permit the regulation ofthe passage of the particles which enter these conduits or sluices,members in the form of perforated masks may be applied around the supplytubes along the length thereof, which permit any desired adjustment ofthe orifices through which the particles pass.

In another embodiment of the invention, the apparatus for FIG. I is aview of a mass of interlocked mineral fibers, on a greatly enlargedscale, with binding agents incorporated therein,

FIG. 2 is a view similar to FIG. 1, following the compression of themass of fibers in a vertical direction;

FIG. 3 is a view similar to FIG. I with the inclusion of separate hardand indeformable particles in the network ofthe mineral fibers, inaccordance with the invention;

FIG. 4 is a view similar to FIG. 3 following the deformation of the massof fibers by a compressive force of the same intensity as that employedon the mass shown in FIG. 2;

FIG. 5 is a front elevation, with certain'parts in section, of anapparatus for executing the invention;

FIG. 6 is a sectional view, with certain parts in elevation, of a secondembodiment of an apparatus in accordance with the invention;

FIG. 7 is a partial view of FIG. 6, on an enlarged scale, at the outletof the receptacle and blower for the hard particles;

FIG. 8 is a front elevation of another embodiment of the invention,illustrating the incorporation of the granules within the mass of fibersissuih g from a different form of fiberp v i s rrow I FIG. 9 is aperspective view of still another embodiment of the invention; I

FIG. 10 is a vertical sectional view through the installation shown inFIG. 9, with certain parts in elevation;

FIG. 11 is a diagrammatic plan view of the distributor shown in FIGS. 9and I0, and indicating schematically the disposition of the conduits orsluices for feeding the hard particles thereto;

FIG. 12 is a vertical sectional view of a portion of the distributorcrown at the outlet end of the. supply conduits, illustrating the flowof the particles onto the distributor surface;

FIG. 13 is a vertical sectional view along line 13-13 of FIG.

FIG. 14 is a sectional view of one of the perforated masks which aremounted along the supply tubes shown in FIGS. 9 and 10;

FIG. 15 is a side view of the mask shown in FIG. I4;

FIG. I6 is a perspective view of another embodiment of the invention;and

'FIG. I7 is a sectional view along line 17- 17 of FIG. 16.

FIGS. 1 to 4 illustrate graphically the advantageous features of theinstant invention. a

FIG. 1 shows a part of a mass of mineral fibers 1 which, as is known,are joined together at cross-points by a binden-Four of thesecross-points are marked A B C D. If this mass is subjected to amechanical stress, such as, for example, compression, (FIG. 2), it isseen'that the thickness of the mesh or lattice-work of fibers decreases,and that the quadrilateral A B C D is reduced to form quadrilateral A BC D.

FIG 3 shows the same fibrous structure as that shown in FIGS. I and 2,but one in which hard, whole and indeforrnable particles or granules 2are introduced and interlocked between the meshes of the network offibers. The preceding cross-points are marked A" B" C" D" and occupysubstantially the same relative positions as the cross-points indicatedin FIG. I. If the mass is subjected to the same compressive stress asthat imposed on the unit shown in FIG. 2, the resulting product isillustrated in FIG. 4. It is seen that the presence of each particleprevents deformation of the mesh in which it is enclosed, the points A'B C' D' remaining in the same positions as points A" B" C" D", and thatthe assembly itself undergoes a decrease in thickness of much lessextent than that in the case illustrated in FIG. 2.

FIG. 5 illustrates one embodiment of an apparatus for obtaining afibrous mass accordingto the invention as shown in FIGS. 3 and 4.

Fibers 2, for example glass fibers, are produced by a machine 3, whichmay be a centrifuge body rotating at'high speed and having a peripheralwall provided with orifices through which are projected by centrifugalforce threads of material which are attenuated into fibers in a mannerwell known in the art. Spray guns 4 project a binding agent onto themass of fibers and a nozzle 5 directs a jet of air onto said mass, todirect it toward the zone where hard granules or particles 12 areintroduced. The particles are contained in a receptacle 6, whose bottomis provided with ledges or movable shutters 7 with a feed regulatordevice 8. The particles issuing from the receptacle pass into a rotatingdrum 9 which assures a regular outflow of the particles wherefrom theyflow by gravity through conduit 10. One or several nozzles II project ajet of air under pressure onto the particles in order to direct themtoward the mass of fibers. A homogeneous spatial distribution of all theparticles within the mass of fibers is assured by controlling thestrength and direction of the air jet.

Spray guns I; may project a binder onto the surfaces of particles beforethey are introduced into the mass of fibers.

The mass of fibers with the particles incorporated therein then passesonto an endless cloth band support or other airpermeable conveyor 14,under which is arranged a suction casing 14a to form a pad or mat I5 ofthe desired thickness.

The passage of this pad into an oven results in polymerization andhardening of the binder and cohesion of the interengaging fibers of themat at their points of crossing contacts.

In the embodiment shown in FIGS. 6 and 7, particles 12 are distributedfrom an annular container 16 arranged coaxially with respect to the massof fibers 2 issuing from a centrifuge 17. The outflow of these particlesis controlled by regulating elements 18. The particles flowing fromannular orifice 19 of the distributor are subjected to the action of acircular blower 20 which assures their homogeneous spatial distributionin the entire mass of fibers.

An annular conduit or tuyere 21 is disposed below the circular blower 20through which the mass of fibers passes, and an oscillating movement isimparted to the former. The moving conduit 21 makes possible a regulardistribution of fibers on the endless air-permeable conveyor 14 for thepurpose of forming the mat thereon.

In this embodiment the binder is introduced into the combined mass offibers and granules by means of spray guns 22.

In the embodiment shown in FIG. 8, the fibers are produced by drawingout the molten glass threads flowing from fixed spinning orifices 23.These threads, transformed into fibers, are directed to the interior ofhood or funnel 24 and are impregnated with a binding agent by means ofspray guns 25 before dropping onto endless conveyor member 26, underwhich is disposed the suction casing 27.

The solid indeformable particles issuing from an apparatus, such asshown in FIG. 5, are led to the interior of the hood 24 where they dropin a free fall in order to be distributed in the mass of fibers by meansof a gas current issuing from one or several nozzles 28.

In the embodiment shown in FIGS. 9 to 17, the apparatus for theproduction of the glass fibers 2 is indicated at 17. and is similar tothat shown generally in FIG. 6. This apparatus 17 consists ofa rotatablecentrifuge operating at high speed with a peripheral wall having aplurality of orifices through which are projected the molten filamentsof glass which are attenuated into the form offibers.

In the apparatus shown in FIGS. 9 to 15, the solid particles, forexample sand, which are introduced into the mass of fibers, are suppliedby two hoppers from which they flow into a pair of tubular conduits 31.A conveyer screw 32 is provided in each of the conduits, the diameter ofwhich is less than the internal diameter of the conduits. The two screws32 are maintained in synchronism by means of a motor-reducer driverassembly 43.

The tubular conduit 31 have orifices 33 (FIG. 13) disposed along thelowermost portions of their cylindrical surfaces and through which flowthe particles which are conveyed by the screws 32. A sluice or conduit34 is disposed opposite each orifice 33. The particles fiow along thelength of each conduit and are discharged in the form of jets onto thedistributor crown 35. This crown is disposed coaxially with the rotarycentrifuge 17 and presents an oblique wall 36 towards the interior, theslope of which is at least equal to the angle of repose ofthe granulesor particles.

The conduits or channels 34 are so disposed that the zones of impact 37of the particles on the oblique wall 36 of the crown are such that theparticles flow freely on this wall, forming sheets 38 which spread outand reunite along the length of the lower edge of the wall 36, (FIG.12), thus forming a homogeneous and continuous sheet. The gaseous jetissuing from the annular orifice 40, provided at the base of thedistributor 35 with the annular chamber 41, acts on this annular sheetof granules. The gas is introduced into this chamber through conduits 42which are disposed obliquely in such a fashion that the particles areprojected into the mass of fibers in the opposite rotary direction fromthat of the rotating mass of fibers.

The mass of fibers in which the particles are thus distributed inhomogeneous fashion then passes into a conduit or tuyere 44 whichexecutes an oscillating movement about a horizontal axis 45, therebypermitting a uniform distribution of the fibers onto a receiving webbelow it, on which is formed a mat, these fibers having been impregnatedpreviously with a binder by means of spray guns, as shown in thearrangements described above.

FIG. 11 shows the disposition of the conduits or channels 34, theinclinations of which are adjusted in a manner that their slope permitsthe natural flow of the particles, (a slope of at least 30 in the caseof sand), and the directions of which are such that the zones of impactlead to the obtention of a continuous and homogeneous sheet, asdescribed above and as shown in FIG. 12. These troughs are mounted onsupports 46 disposed above the distributor crown in a fashion tominimize the obstruction of the apparatus.

The disposition of the conveying screws 32 and their rotary speed suchthat a stream of particles of substantially uniform thickness isobtained below the assembly of outlet orifices 33 of tubular conduits31. However, to obtain the proper delivery from each channel 34, whichis fed from each of the orifices, masks 47, having openings 48 ofdifferent diameters, are resiliently mounted on the tubular conduits 31in overlying relation to openings 33 therein. These masks of springymaterial may be turned to place an orifice of predetermined sizeopposite each outlet opening 33 ofthe tubular conduit according to therate of discharge sought to be attained. An abutment or lug 49 isprovided on the inside of each mask for selective cooperation with oneof a plurality of grooves or notches 50 on the periphery of the conduits31, which permits placing the apertured mask in correctly alignedposition for any selected opening 48 in the latter.

In order to permit the evacuation of any excess particles or granulesand to avoid jamming or choking of the conduits 31, the end 52 of eachconduit is provided with openings 51 which permits the eliminationofthese excess particles.

The quantity of granules 0r particles discharged from the distributor isa function of the diameter of the holes 48 in the masks and the speed ofrotation of the feedscrews 32, the latter being adjusted for all theholes, with the exception of the openings 51 which are effective onlywhen the conduits are too full. The latter serve to discharge particlesonly when the holes 33 and 48 become obstructed or when there is astrained operation, thereby avoiding a breakage of the feedscrews.

In the modified embodiment shown in FIGS. 16 and 17, the particles arefed from a hopper 53 into an annular conduit 54 arranged in the form ofa torus, in which operates a helical coreless feed member 55 which isrotated by a motor-reducer device 56. This conduit is disposed coaxiallywith the rotary centrifuge adjacent to the inclined wall 36 of thedistributor crown 35, which operates in the same manner as describedabove in conjunction with FIGS. 9 to 15. The conduit 54 is provided withorifices 57, (FIG. 17), through which the particles flow onto the wall36 for forming a continuous sheet of uniform thickness at the internalrim 39 of the distributor crown.

Any suitable polymerizable resins may be used as binding agents,examples of which are set forth below. Furthermore, variations may bemade in the details ofthe apparatus, for example, in the character ofthe air-permeable conveyor for receiving the mass of fibers combinedwith a resin binder and hard particles distributed therethrough. As setforth above, the latter may be in the form of hard solid andindeformable granules, such as sand, or these granules may be hard andindeformable with voids therein such as foamed or porous granules ofperlite or vermiculite. The invention also contemplates the use of hardand indeformable light particles which are interlocked in the meshes ofthe fibrous network, such as crushed, foamed or porous glass.

Below are given examples of products ofglass fibers according to theinvention as well as comparative data, between these products and thesame products which do not include hard and separate unitary solid orfoamed indeformable particles, from the point of view of heat-insulatingcapability and resistance to deformation.

EXAMPLE I a, Composition of glass SiO 66.371 Ago, 3.0% r 0, 0.4% CaO7.6% M30 3.4% mm tam K,o 1.1% 3,0, 1.59; BaO 2.0%

b. Mean diameter of fibers: 6 microns c. Nature of binder: Phenolformaldehyde resin d. Nature of particles: Sand e. Mean diameter ofgrains: 0.2 mm.

Coefiicient Load required Composition of thermal to reduce thickofproduct, conductivity, ncss oi product Product kg./m. KcaL/m. C. by 25%,kgJmJ Product without {Fibers 38 28. 7 470 sand. Resin: 2.-.

Fibers: 38- Product with sand.. Resin: 2 30. 2 880 Sand: 6

NOTE.Kg./mis abbreviation for kg. per cubic meter. Kg./r11. isabbreviation for kg. per square meter.

It is to be noted that while the products have substantially the sameinsulating power, the load necessary to obtain the same reduction inthickness in the product in accordance with the invention is nearlydouble.

EXAMPLE II a. Composition of the glass b. Mean diameter of the fibersidentical with c Nature of the binder those of Example I (d) Nature ofthe granules or particles e. Mean diameter of the granules CoefiicicntLoad required Composition of thermal to reduce thickof product,conductivityv ness of product Product kg. In. Kcal. m. C. by 25%, kg. m5

Product without {Fibersz 54.6 N} 28.0 1, 510

sand. Resin: 5:5". Fibers: 54.5

Product with sar1d Resin: 5.5. 31.0 2. 300

Sand: 90

EXAMPLE ill a. Composition of the glass Sill (H.39 Alp, 5.50? F 0, 0.69?Ca 7.35 MgO 3.1% Nai .0 i399 K 0 LQCi B 0 23% 8210 3.2%

b. Mean diameter at the fibers: l2 microns c. Nature of binder: Phenolformaldehyde resin d. Nature of granules; Sand e. Mean diameterofgranules: 0.2 mm.

Set forth below are two examples of products of glass fibers withperlite and vermiculite, according to the invention, these examplesshowing, comparatively, the differences from the point of viewofinsulating value and resistance to deformation between these productsand the same products which do not include these particles.

EXAMPLE IV a. Composition of glass SiO- 69.0% A1 0 2.3% no 0.4; Call9.0% MgO 2.9% N21,!) K 0 0.2% 13,0 L7; F, 0.5%

b. Mean diameter of fibers 6 microns 4:. Nature of binder Phenolformaldehyde resin d. Nature ol'gratns Perlite e. Diameter of grains U.lmm. to 2 mm.

Coctiicicnt Load required Composition of thermal to roduco thickofproduct, conductivity, ness of product Product kg. ru. Kcal. m. C. by25%, k n/m.

Product without {Fibersz 3G .-l 28. 7 800 perlitc. Resin: 4 Product withFibers:

pcrlito. {Re-sin: 30. 0 2, 200

Pcrlitc: 18

it is to be noted that while both products have substantially the sameinsulating capacity, the load required to attain the same reduction inthickness is nearly tripled for the product in accordance with theinstant invention.

EXAMPLE V :1. Composition of glass Identical to those of h Mean diameterof fibers Example I\' c. Nature of hinder d. Nature of grainsvermiculite 0. Diameter ol'grains from 3 mm. to 6 mm COBlllClGnt- Loadrequired 1. The method of producing bodies of insulating material ofinterlaced mineral fibers agglomerated with a hardened resin binder andthrough which are homogeneously interspersed separate hard andindcformable particles, which comprises,

a. forming a curtain of freshly formed mineral fibers andgravitationally depositing them onto a travelling support,

b. dropping a stream of hard and indeformable particles adjacent to saidfalling curtain of fibers and blowing said particles into said fibers tohomogeneously distribute said particles within the body of fibers beforethe combined fibers and particles are deposited on the travellingsupgrojeeting a hardenable binder onto the curtain of fibers andparticles prior to their deposition on the travelling support, and

. reducing the volume of the combined mass of fibers with the binder andhard particles interspersed therethrough preparatory to the hardening ofsaid combined mass.

2. The method set forth in claim 1 wherein the depositing of the mineralfibers is executed on an air-permeable travelling support and theconcluding step of reducing the volume of the combined mass is executedby suction effects exercised on said mass through said support.

3. The method set forth in claim 2 wherein a mass of freshly formedmineral fibers drops from a fiberizing apparatus, and the projection ofthe hardenable binder is executed by spraying a polymerizable organicresin into the falling mass of fibers in the course of travel of themass to the support 4. The method set forth in claim 3 wherein thespraying of the resin into the mass of fibers is executed following theincorporation of the hard particles therein by blowing said particlesinto said mass.

5. The method set forth in claim 3 wherein the projection of thehardenable resin binder is executed by spraying said binder onto saidhard and indeformable particles prior to the introduction of the latterinto the mass of fibers.

6. The method set forth in claim 5 including the spraying of apolymerizable organic resin into the mass of fibers prior to theintroduction thereinto of the coated hard particles.

7. The method set forth in claim 2 wherein the mass of freshly formedmineral fibers drops from a fiberizing apparatus and the introduction ofthe hardenable binder and the hard and indeformable particles into themass of fibers is executed at different points of travel of the fallingmass of fibers.

8. The method set forth in claim 7 wherein the mass of fibers drops inthe form of a rotating annular curtain from a centrifuging apparatus andthe hard and indeformable particles are blown into the falling curtainin the form of an annular sheet surrounding said curtain.

9. The method set forth in claim 18 wherein the falling annular curtainof fibers with the hard indeformable particles therein is oscillated toand for to effect a smooth deposition of the mass offibers onto thetravelling support.

10. The method set forth in claim 9 wherein the hardenable binder issprayed onto the oscillating curtain of fibers immediately before thedeposition thereof onto the travelling support.

11. The method set forth in claim 7 wherein the mass of fibers drops inthe form of a rotating annular curtain from a centrifuging apparatusrotating in one direction, and the hard and indeformable particles areblown into the falling curtain in the form of an annular sheet having acomponent of rotary motion in the opposite direction.

12. The method set forth in claim 11 wherein the falling annular curtainof fibers with the hard indeformable particles therein is oscillated toand Fro to effect a smooth deposition of the mass of fibers onto thetravelling support.

13. The method set forth in claim 12 wherein the hardenable binder issprayed onto the oscillating curtain of fibers immediately before thedeposition thereof onto the traveling support.

14. The method set forth in claim 1 wherein the hard and indeformableparticles are selected from a group of materials consisting of sand,crushed glass, crushed rock, perlite. and vermiculite.

15. The method set forth in claim 1 wherein the quantity of the hard andindeformable particles is varied in dependence upon the mechanicalcharacteristic sought to be imparted to the bodies of insulatingmaterial.

16. The method set forth in claim 15 wherein the granulometry of thehard and indeformable particles is varied in dependence on the size ofthe mineral fibers and the physical properties sought to be imparted tothe insulating material.

17. The method of producing bodies of insulating material of interlacedmineral fibers ag lom'erated with a hardened resin binder and throughWlllC are homogeneously interspersed separated hard and indeformableparticles, which comprises,

a forming a curtain of freshly formed mineral fibers and gravitationallydepositing them onto a travelling support,

b. dropping a stream of hard and indeformable particles adjacent to saidfalling curtain of fibers and blowing said particles into said fibers tohomogenously distribute said particles within the body of fibers beforethe combined fibers and particles are deposited on the travellingsupport,

c. projecting a hardenable binder onto the curtain of fibers prior tothe combination of the hard particles therewith and the depositionthereof on the travelling support, and

d. reducing the volume of the combined mass of fibers with the binderand hard particles interspersed therethrough preparatory to thehardening of said combined massv 18. The method of producing bodies ofinsulating material of interlaced mineral fibers agglomerated with ahardened resin binder and through which are homogeneously interspersedseparate hard and indeformable particles, which comprises,

a forming a curtain of freshly formed mineral fibers and gravitationallydepositing them onto a travelling support,

b. dropping a stream of hard and indeformable particles adjacent to saidfalling curtain of fibers and blowing said particles into said fibers tohomogeneously distribute said particles within the body of fibers beforethe combined fibers and particles are deposited on the travellingsupport,

c. projecting a hardenable binder onto the stream of hard particlesprior to the combination thereof with said curtain of fibers and thedeposition thereof on the travelling support, and

d. reducing the volume of the combined mass of fibers with the binderand hard particles interspersed therethrough preparatory to thehardening of said combined massv UNITED STATES PATENT OFFICE 569CERTIFICATE OF CORRECTION Patent No. 3 3 Dated October 26, 1971Inventor(s) CLAUDE WEB and ALAIN BONNET It is certified that errorappears in the above-identified patent and that said Letters Patent arehereby corrected as shown below:

In claim 9, column 9, line 33, change "18" to --7--.

In claim 9, column 9, line 35, change "for" to --fro--.

In claim 12, column 9, line 50, change "Fro" to --fro--.

Signed and sealed this 27th day of June 1972.

(SEAL) Attest:

EDWARD M.FLETCHER, JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents

2. The method set forth in claim 1 wherein the depositing of the mineralfibers is executed on an air-permeable travelling support and theconcluding step of reducing the volume of the combined mass is executedby suction effects exercised on said mass through said support.
 3. Themethod set forth in claim 2 wherein a mass of freshly formed mineralfibers drops from a fiberizing apparatus, and the projection of thehardenable binder is executed by spraying a polymerizable organic resininto the falling mass of fibers in the course of travel of the mass tothe support
 4. The method set forth in claim 3 wherein the spraying ofthe resin into the mass of fibers is executed following theincorporation of the hard particles therein by blowing said particlesinto said mass.
 5. The method set forth in claim 3 wherein theprojection of the hardenAble resin binder is executed by spraying saidbinder onto said hard and indeformable particles prior to theintroduction of the latter into the mass of fibers.
 6. The method setforth in claim 5 including the spraying of a polymerizable organic resininto the mass of fibers prior to the introduction thereinto of thecoated hard particles.
 7. The method set forth in claim 2 wherein themass of freshly formed mineral fibers drops from a fiberizing apparatusand the introduction of the hardenable binder and the hard andindeformable particles into the mass of fibers is executed at differentpoints of travel of the falling mass of fibers.
 8. The method set forthin claim 7 wherein the mass of fibers drops in the form of a rotatingannular curtain from a centrifuging apparatus and the hard andindeformable particles are blown into the falling curtain in the form ofan annular sheet surrounding said curtain.
 9. The method set forth inclaim 18 wherein the falling annular curtain of fibers with the hardindeformable particles therein is oscillated to and for to effect asmooth deposition of the mass of fibers onto the travelling support. 10.The method set forth in claim 9 wherein the hardenable binder is sprayedonto the oscillating curtain of fibers immediately before the depositionthereof onto the travelling support.
 11. The method set forth in claim 7wherein the mass of fibers drops in the form of a rotating annularcurtain from a centrifuging apparatus rotating in one direction, and thehard and indeformable particles are blown into the falling curtain inthe form of an annular sheet having a component of rotary motion in theopposite direction.
 12. The method set forth in claim 11 wherein thefalling annular curtain of fibers with the hard indeformable particlestherein is oscillated to and Fro to effect a smooth deposition of themass of fibers onto the travelling support.
 13. The method set forth inclaim 12 wherein the hardenable binder is sprayed onto the oscillatingcurtain of fibers immediately before the deposition thereof onto thetraveling support.
 14. The method set forth in claim 1 wherein the hardand indeformable particles are selected from a group of materialsconsisting of sand, crushed glass, crushed rock, perlite, andvermiculite.
 15. The method set forth in claim 1 wherein the quantity ofthe hard and indeformable particles is varied in dependence upon themechanical characteristic sought to be imparted to the bodies ofinsulating material.
 16. The method set forth in claim 15 wherein thegranulometry of the hard and indeformable particles is varied independence on the size of the mineral fibers and the physical propertiessought to be imparted to the insulating material.
 17. The method ofproducing bodies of insulating material of interlaced mineral fibersagglomerated with a hardened resin binder and through which arehomogeneously interspersed separated hard and indeformable particles,which comprises, a forming a curtain of freshly formed mineral fibersand gravitationally depositing them onto a travelling support, b.dropping a stream of hard and indeformable particles adjacent to saidfalling curtain of fibers and blowing said particles into said fibers tohomogenously distribute said particles within the body of fibers beforethe combined fibers and particles are deposited on the travellingsupport, c. projecting a hardenable binder onto the curtain of fibersprior to the combination of the hard particles therewith and thedeposition thereof on the travelling support, and d. reducing the volumeof the combined mass of fibers with the binder and hard particlesinterspersed therethrough preparatory to the hardening of said combinedmass.
 18. The method of producing bodies of insulating material ofinterlaced mineral fibers agglomerated with a hardened resin binder andthrough which are homogeneously interspersed separate hard andindeformable particles, which comprises, a formiNg a curtain of freshlyformed mineral fibers and gravitationally depositing them onto atravelling support, b. dropping a stream of hard and indeformableparticles adjacent to said falling curtain of fibers and blowing saidparticles into said fibers to homogeneously distribute said particleswithin the body of fibers before the combined fibers and particles aredeposited on the travelling support, c. projecting a hardenable binderonto the stream of hard particles prior to the combination thereof withsaid curtain of fibers and the deposition thereof on the travellingsupport, and d. reducing the volume of the combined mass of fibers withthe binder and hard particles interspersed therethrough preparatory tothe hardening of said combined mass.